Refrigerant compressor



Jan, 4am? LGIBJZI 1F. OPPMAN REFRIGERANT COMPRESSOR Filed Sept. 5, 192a 2 Sheets-Sheet 1 Jan, 4, 11927, 3,13 1% F. OPPMAN' REFRIGERANTICOMPRESSOR Filed Sept. 5, 1926 2 sheetssheet 2 K WW,

Fran/f @vpmz,

Patented Jan. 4, 1 927.-

UNITED} S A ES v 1,613,121 PATENT OFFICE.

'i tnnxorrmnn, or GARY, INDIANA.

REFRIGERAN'J. COMPRESSOR.

' Application filed September 3, 1926. Serial No. 133372.

This invention relates torefrigerant compressors and has for its object the provislon of an eiiicient compressor of simplified de sign capable of being manufactured and sold 5 at a material reductioncomp'ared with the A still further feature of the invention consists in the provision of means for placing the crank case in communication with the cylinder intake .port during the suction stroke of the piston whereby gases that have leaked into the crank case are extracted therefrom and the development of excessive pressure in the crank case prevented.

Other characteristics and advantages of the invention will bemore readily apparent from the following detailed description and accompanying drawings, in which,

Figure 1 is a view partly in vertical section and partly-in side elevation of acom- 3 pressor constructed in accordance with my invention;

Figure '2 is a vertical sectional view through the compressor taken at right angles to the sectional plane of Figure 1 and,

Figure 3 isa detailed view of a portion of the intake valve structure.

Proceeding now to a more detailed discussion of the drawings 5 designates the compressor cylinder which is cast integralwith the crank case 6. The latter is formed with a su table sustaining base 7 and is permanently closed at one side by the integral wall 8. At the other side the. crank case is closed by a removable interfitting plate or head 9 45 secured in place by bolts 10 or equivalent fastenings with suitable packing 11- clamped between the crank case and the inner surfaces of the plate or head 9 to prevent leakage. The wall 8 of the crank case is formed porting one.end of a crank shaft13 having its other end passing through the bearing 14 formed in the head 9. Bearing 14 is extended outwardly from the head 9 to provide a stufiing box 15 containing suitable packing 16 held in place by the gland ring 17 and into the crank case is reduced to aminimum.

with an integral cup shaped bearing 12 supthe gland nut 18. The packing 16 may be of i any desired nature but it is preferredto use Bi packing of the Cooke seal ring type.

The crank shaft 13 is connected by the usual pitman'19 to a piston 20 operatingin the cylinder 5. In order to reduce to a minimum leakage of the refrigerant into the crank case I provide-the piston with four packing rings'21 located above the wrist pin 22 and with a further packing ring 23 mounted in the skirt portion of the piston below said wristpin. I find that this arrangement of packing rings is moreefi'ecti've than the arrangement'usually employed wherein all of the rings are located a considerable distance above'the skirt portion or lower end of 4 the piston.

At its upper end the cylinder 5 is provided with a flange 24 which is secured by the bolts 25 to the base flange 26 of a separable cast cylinder head 27. The cylinder head is formed with two parallel passages extending vertically ,therethrough and forming, respectively, an intake port 28- and a discharge port 29. The intake port communicates with the refrigerant supply passage 30 passing diagonally'through the head as shown in Figure 2 and connected at its outer terminal to the refrigerant supply conduit 31. Im-- mediately adjacent its connection to the passage 30 the supply conduit 31 is provided with a branch 32 leading downwardly to and throughan opening 33 formed in the upper part of the wall 8 of the crank case. The end of the branch 32 which protrudes into the crank case is closed except for the relatively small opening 33, the purpose of which is hereinafter described. Branch 32 is preferably equipped with acheck valve 32' which serves to prevent leakage of gas or liquid into the crank case through said branch and also to permit escape of any gas pressure formed in the crank case by leakage of gas past the piston.

Threaded into and closing the upper end of the inlet passage 28 is a hollow plug 34 formed with an intermediate tapered portion 35 fitting a correspondingly tapered portion 36 formed at the upper end of said pas- T sage whereby a tight fit is obtained between the plug and the cylinder head to preventnuts 40. Below the nuts the valve stem is encircled by a sleeve 41 having its upper end enlarged and supported upon a coil spring 42 having its lower terminal resting upon a disc 43 which in turn is supported on a shoulder 44 formed in the passage near the valve seat. The disc 43 is provided with a central guide opening receiving the valve stem therethrough and with a plurality of relatively small openings surrounding the central opening and through which the refrigerant passes into the cylinder during the suction stroke of the piston.

The discharge valve 45 closes downwardly against a seat 46 formed at the lower end of discharge passa e 49. The stem 47 of the valve is slidile in a guide bore 48 formed in a plug 49 threaded into and closing the upper end of the discharge passage,

sald plug and the upper end of the passage being formed to provide tapered surfaces 50 whereby a tight fit is obtained. The valve 45 is held in closed position by a coil spring 51 having its lower end resting upon the valve proper and its upper end engaging the shoulder 52 of the plug. The discharge passage 29 communicates with a diagonal port 53 extending through the head and adapted to be connected with the usual refrigerant circulating apparatus.

In the operation of the compressor intake valve 37 opens automatically against the resistance of spring 42 during the suction stroke of the piston 20 and the refrigerant supplied through the conduit 31 is drawn into the cylinder above the piston. At the same time the suction created in the branch 32 serves to deliver to the upper end of the cylinder any refrigerant or gases that may have leaked past the piston into the crank case. During the upward or compression stroke of the piston the suction valve closes and the discharge valve 45 opens in the usual manner to ermit the compressed refrigerant to be delivered from the compressor through the discharge passage 29.

From the fore olng it will be apparent that the design 0% the cylinder head is such that the various elements of the intake and discharge valves may be assembled therewith ordetached therefrom without requiring a great deal of time or work and the construction and assembly of such elements is also suchas to materially reduce cost of production as compared with the valve structures of-standard compressors. The provision of this type of head together with the feature of casting the cylinder in one piece with the crank case results in the production of a very economical and efficient type of compressor. The arrangement of the piston rings and the provision of the branch connection between the crank case and the intake serves, as previously explained, to prevent accumulation of gases in said crank case during operation of the compressor.

Having thus fully described what ll now consider to be the preferred embodiment of my invention it will be understood that various changes may be resorted to in the construction, combination and arrangement of parts without departing from the scope of the invention as defined by the appended claim.

,What I claim is:

A head for refrigerant compressor cylinders comprising a casting formed with parallel intake and discharge valve passages extending from the outer to the inner surfaces of the head, said head being further formed at opposite sides with lateral passages communicating at their inner ends with said intake and discharge passages, said intake passage being formed at its inner end with an inwardly facing valve seat and said discharge passage being formed at its inner end with an outwardly facing valve seat, valves engaging said seats, valve stems carried by said valves, hollow plugs threaded into and closing the outer ends of said passages and serving to receive and guide the outer ends of said stems, a spring confined between the discharge valve and an opposing portion of the plug closing the outer end of the discharge passage, a sleeve loosely mounted on the intake valve stem and having its outer end enlarged to form an inwardly facing annular shoulder, means limiting outward movement of said sleeve relative to said stem, and a spring mounted in the intake valve passage with the outer end of said spring engaging said shoulder and the inner end of the spring bearing against a suitable abutment provided within said passage.

In testimony whereof I hereunto aflix my signature.

FRANK OPPM'AN. 

